The long-range goal of this competing continuation proposal is to assess and improve the breast tumor screening, diagnostic and monitoring capabilities of diffuse optical tomography (DOT) with near infrared (NIR) light. Near-infrared diffuse optical tomography is based on the study of functional processes and provides several unique measurable parameters with potential to enhance breast cancer detection and characterization sensitivity and specificity. In particular, DOT provides functional information directly related to tumor patho- physiology (e.g. metabolic activity, angiogenesis, and blood flow/concentration). This information can be complementary to structural and functional information provided by traditional medical imaging. Furthermore unlike many diagnostic methods, DOT techniques utilize non-ionizing radiation, are non-invasive, and are often technologically simple and fast. Thus, as more information is acquired and analyzed, we expect diffuse optics to find a variety of niche applications in screening, diagnosis and cancer therapy monitoring. The proposed research builds on initial success and aims to continue to improve and explore DOT by implementing novel statistical analysis methods, by examining associations between histopathology and optical tumor signatures, by introducing a much-improved Generation II instrument into the clinic, and via pilot clinical studies exploring exogenous contrast agent imaging and neoadjuvant chemotherapy monitoring. The proposed research will derive patients from ongoing clinical trials and from the normal patient population at the Hospital of the University of Pennsylvania (HUP). The research includes the development of breast-DOT computer aided detection (CAD) analyses and software; in addition a range of patient-intensive (rather than exploratory) clinical trials are planned. Primary clinical studies (~100 patients, 50 normal subjects) will acquire data from normal and tumor bearing patients based on endogenous contrast. Pilot clinical studies will follow tumor progression during neoadjuvant chemotherapy (~25 patients, 25 normal subjects) and will measure fluorescence from an exogenous contrast agent, Indocyanine Green, as it washes into and out-of the tumor bearing breast (~50 patients, 25 normal subjects). Overall, the project will provide basic information needed for the design of more comprehensive, future DOT clinical trials. PUBLIC HEALTH RELEVANCE: Approximately one in eight women in the United States will develop breast cancer, and of these about 30% will ultimately die of the disease. Despite considerable scientific progress, new technologies are still desirable to detect breast cancers earlier for treatment, to detect cancers missed by screening mammography, to improve cancer diagnosis and staging in selected situations, and to track tumor progression during cancer therapy and to assist in therapy planning. The long-range goal of this grant is to assess and improve the breast tumor screening, diagnostic and monitoring capabilities of diffuse optical tomography with near infrared light.